1. Field of the Invention
The present invention relates to an illumination device used to illuminate a main subject during a photographing operation, an image-capturing system, a camera system and a camera.
2. Description of the Related Art
There is a camera known in the related art that illuminates a main subject with an illumination device that uses an LED-type instead of a discharge-type illumination device such a xenon discharge tube (see Japanese Laid Open Patent Publication No. 2002-207236). In the camera disclosed in Japanese Laid Open Patent Publication No. 2002-207236, the quantity of light to be emitted from the illumination device is determined based upon the subject distance measured by a range finding device and the film sensitivity. The publication discloses that the light quantity is controlled by varying the number of LEDs driven, the value of the electrical current which drives the LEDs and the length of time over which the LEDs emit light.